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991.
ABSTRACT There is growing interest in personality profiles associated with morningness–eveningness to foster an understanding of the behaviors and mental states of chronotypes. This study aimed to analyze the domains of emotionality, activity and sociability (EAS) temperament in relation to morningness–eveningness in adolescents. A sample of 539 school pupils aged 13–19 years completed the EAS Temperament Survey, the Composite Scale of Morningness and the Munich Chronotype Questionnaire. Amongst the five EAS domains (emotionality-distress, emotionality-fearfulness, emotionality-anger, activity and sociability), greater emotionality-anger was related to eveningness, while greater emotionality-distress was related to lower social jet lag. The results suggest that evening chronotypes can be temperamentally inclined to anger. The possible mechanisms of this association are discussed. 相似文献
992.
Asgar Ergin Konrad Büssow Joachim Sieper Andreas Thiel Rainer Duchmann Thomas Adam 《Microbial cell factories》2007,6(1):18
Background
Genetic factors and a dysregulated immune response towards commensal bacteria contribute to the pathogenesis of Inflammatory Bowel Disease (IBD). Animal models demonstrated that the normal intestinal flora is crucial for the development of intestinal inflammation. However, due to the complexity of the intestinal flora, it has been difficult to design experiments for detection of proinflammatory bacterial antigen(s) involved in the pathogenesis of the disease. Several studies indicated a potential association of E. coli with IBD. In addition, T cell clones of IBD patients were shown to cross react towards antigens from different enteric bacterial species and thus likely responded to conserved bacterial antigens. We therefore chose highly conserved E. coli proteins as candidate antigens for abnormal T cell responses in IBD and used high-throughput techniques for cloning, expression and purification under native conditions of a set of 271 conserved E. coli proteins for downstream immunologic studies. 相似文献993.
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Neurons in the sensory system exhibit changes in excitability that unfold over many time scales. These fluctuations produce noise and could potentially lead to perceptual errors. However, to prevent such errors, postsynaptic neurons and synapses can adapt and counteract changes in the excitability of presynaptic neurons. Here we ask how neurons could optimally adapt to minimize the influence of changing presynaptic neural properties on their outputs. The resulting model, based on Bayesian inference, explains a range of physiological results from experiments which have measured the overall properties and detailed time-course of sensory tuning curve adaptation in the early visual cortex. We show how several experimentally measured short term plasticity phenomena can be understood as near-optimal solutions to this adaptation problem. This framework provides a link between high level computational problems, the properties of cortical neurons, and synaptic physiology. 相似文献
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Konrad P. Mielke Tom Claassen Michela Busana Tom Heskes Mark A. J. Huijbregts Kees Koffijberg Aafke M. Schipper 《Ecography》2020,43(12):1741-1751
Species distribution models (SDMs) are frequently used to understand the influence of site properties on species occurrence. For robust model inference, SDMs need to account for the spatial autocorrelation of virtually all species occurrence data. Current methods do not routinely distinguish between extrinsic and intrinsic drivers of spatial autocorrelation, although these may have different implications for conservation. Here, we present and test a method that disentangles extrinsic and intrinsic drivers of spatial autocorrelation using repeated observations of a species. We focus on unknown habitat characteristics and conspecific interactions as extrinsic and intrinsic drivers, respectively. We model the former with spatially correlated random effects and the latter with an autocovariate, such that the spatially correlated random effects are constant across the repeated observations whereas the autocovariate may change. We tested the performance of our model on virtual species data and applied it to observations of the corncrake Crex crex in the Netherlands. Applying our model to virtual species data revealed that it was well able to distinguish between the two different drivers of spatial autocorrelation, outperforming models with no or a single component for spatial autocorrelation. This finding was independent of the direction of the conspecific interactions (i.e. conspecific attraction versus competitive exclusion). The simulations confirmed that the ability of our model to disentangle both drivers of autocorrelation depends on repeated observations. In the case study, we discovered that the corncrake has a stronger response to habitat characteristics compared to a model that did not include spatially correlated random effects, whereas conspecific interactions appeared to be less important. This implies that future conservation efforts should primarily focus on maximizing habitat availability. Our study shows how to systematically disentangle extrinsic and intrinsic drivers of spatial autocorrelation. The method we propose can help to correctly identify the main drivers of species distributions. 相似文献
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Konrad A. Szychowski Urszula E. Binduga Kamila Rybczyńska-Tkaczyk Marcin L. Leja Jan Gmiński 《Saudi Journal of Biological Sciences》2018,25(8):1703-1712
Garlic (Allium sativum L., Alliaceae) has acquired a reputation as a therapeutic agent and herbal remedy to prevent and treat several pathologies. The aim of the present study was to determine the effect of two Allium sativum L. cultivars, Harna? and Morado, on reactive oxygen species (ROS) production, viability and apoptotic process in human squamous carcinoma cell line SCC-15. The experiments were conducted on SCC-15 cell line exposed to increasing concentrations of garlic extracts of 0.062, 0.125, 0.250, 0.500 and 1.000 mg/mL. After the experiments, ROS formation, caspase-3 activity and neutral red uptake were measured in the cells, and in a collected medium lactate dehydrogenase (LDH) release was measured. The Spanish cultivar Morado has demonstrated higher potential to stimulate ROS production in SCC-15 cells after a short time period (6 h) than the Polish cultivar Harna?. However, the Polish cultivar Harna? manifested more prolonged potential to stimulate ROS production in SCC-15 cells. Both studied garlic extracts induced cytotoxicity on SCC-15 cell line which was probably ROS-dependent. We also determined that in SCC-15 cells high concentrations of studied extracts did not cause activation of caspase-3 which suggested caspase-independent or necrotic cell death. 相似文献
1000.
Konrad V. Miller Roberto Noguera Jordan Beaver Anita Oberholster David E. Block 《Biotechnology and bioengineering》2020,117(1):109-116
Red wine production begins with a simultaneous fermentation and solid-phase extraction process. Red wine color and mouthfeel is the result of the extraction of phenolics from grape skins and seeds during fermentation, where extraction is a strong function of temperature and ethanol concentration. During fermentation, grape solids form a porous “cap” at the top of the fermentor, resulting in a heterogeneous fermentation system with significant temperature and concentration gradients. In this work, we present a spatial, time-variant reactor engineering model for phenolic extraction during red wine fermentation, incorporating fermentation kinetics, mass transfer, heat transfer, compressible fluid flow, and phenolic extraction kinetics. The temperature and ethanol concentration profiles predicted by this model allow for the calculation of phenolic extraction rates over the course of fermentation. Phenolic extraction predictions were validated against prior experimental data to good agreement and compared to a well-mixed model's predictions to show the utility of a spatial model over well-mixed models. 相似文献